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ANALISI DEI METABOLITI SECONDARI DELLA FLORA SICILIANA CON PARTICOLARE RIFERIMENTO AI TAXA ENDEMICI O RARI
No full textQuesto progetto di ricerca ha avuto l’obiettivo di approfondire la conoscenza sulle piante della flora siciliana, con particolare riferimento ai taxa autoctoni ed endemici o rari e i loro metaboliti secondari. Lo studio ha riguardato soprattutto l’analisi dei componenti volatili e non volatili di specie appartenenti a importanti famiglie botaniche, con un’attenzione specifica alle Apiaceae, Asteraceae, Fabaceae, note per la vastità di specie in esse presenti e il loro difficile inquadramento tassonomico, nonché per la loro diversità chimica e il contenuto di composti bioattivi di rilevante interesse farmacologico e fitoterapico.Un focus particolare è stato riservato all’analisi degli oli essenziali di taxa non precedentemente indagati, che hanno mostrato interessanti applicazioni sia nel campo chemiotassonomico, fornendo supporto alla revisione delle famiglie e dei generi, discriminando tra specie morfologicamente simili, nonché in quello biologico, attraverso l’isolamento e la caratterizzazione dei metaboliti con potenziale applicativo per le attività biologiche che sono state riscontrate. Il presente lavoro fornisce un importante contributoscientifico che arricchisce la conoscenza sulla biodiversità chimica delle piante siciliane, evidenziando come l’integrazione di studi tassonomici, chimici e biologici, sia di fondamentale importanza per la valorizzazione e la tutela di questo straordinario patrimonio floristico.This research project aimed to improve knowledge of Sicilian flora, with particular reference to native, endemic, or rare taxa and their secondary metabolites. The study focused mainly on the analysis of volatile and non-volatile components of species belonging to important botanical families, with specific focus on Apiaceae, Asteraceae, and Fabaceae, known for the wide variety of species found within them and their difficult taxonomic classification, as well as for their chemical diversity and content of bioactive compounds of significant pharmacological and phytotherapeutic interest.Particular emphasis was placed on the analysis of essential oils from taxa not previously investigated, which showed interesting applications both in the chemotaxonomic field, providing support for the revision of families and genera, discriminating between morphologically similar species, and in the biological field, through the isolation and characterization of metabolites with potential applications for the biological activities that were found. This work provides an important scientific contribution that enriches knowledge about the chemical biodiversity of Sicilian plants, highlighting how the integration of taxonomic, chemical, and biological studies is of fundamental importance for the enhancement and protection of this extraordinary floristic heritage
Distributed compressive genomics: Fundamental pattern matching primitives via spark
No full textCompressive genomics leverages compressed data representations to enhance the efficiency of bioinformatics tasks like sequence comparison and search. Surprisingly, the fundamental operation of pattern matching on large DNA sequence collections remains unexplored in the realm of genomic analysis. However, distributed systems like Spark offer the scalability necessary to process increasingly large genomic datasets efficiently. We present the first Spark-based implementation of the FM-Index and Compressed Boyer-Moore (CBM) algorithms, evaluating their performance and providing insights into their advantages for large-scale bioinformatics applications. A comprehensive experimental study demonstrates clear performance gains over uncompressed approaches. Furthermore, we introduce SparkGeco, a distributed compressive genomics software library designed to simplify the integration of FM-Index and CBM algorithms into DNA sequence analysis pipelines within Apache Spark, thus supporting the development of efficient and scalable genomic analysis workflows. This work provides a concrete step towards high-performance, data-centric eScience solutions in computational biology
Magnetic toroidal dipole resonances for efficient THz generation in dielectric metasurfaces
No full textNonlinear dielectric metasurfaces represent a rapidly advancing family of optical devices characterized by high nonlinear conversion efficiency with an ultrathin form factor. Here, we report on terahertz (THz) emission through difference-frequency generation (DFG) in an Aluminum Gallium Arsenide (AlGaAs) metasurface supporting magnetic toroidal dipolar resonances at the two pump wavelengths, which nonlinearly interact with each other. The simultaneous excitation of these high-Q resonances, together with the dispersive behavior of the nonlinear susceptibility, enables an exceptionally strong DFG response. Conversion efficiencies around 8 THz exceed those of an unstructured AlGaAs slab of the same thickness by over nine orders of magnitude. These results highlight the potential of DFG metasurfaces as compact and highly efficient platforms for THz generation
La gara dell'amicizia (tra la Scizia e la Grecia, secondo Luciano)
No full textWe could discern the meritocratic logic underlying the practice of sporting encounters in the exchange of words between interlocutors, such as, for example, the conversation in Lucian's Toxaris. Thus, based on the oppositional dichotomy between the Greeks and the Scythians, a sort of oratorical contest is waged. However, towards the conclusion of the dialogue, both contenders willingly declare themselves equal winners, with a view to mutual satisfaction. In this way, no one is defeated, and the win-lose logic of athletic activity is clearly rejected in favour of a positive-sum game (win-win), thus ensuring a commitment to the creation of a future of shared happiness and well-being
Towards ethical agribusiness: disentangling new patterns of consumption, governance and policy actions
No full textL’obiettivo di progredire i sistemi alimentari verso produzioni più eticamente responsabili è una delle questioni più complesse della nostra epoca, tanto da porre la promozione del lavoro dignitoso come obiettivo dell'Agenda 2030 (SDG 8). Il settore agricolo è particolarmente vulnerabile a condizioni di lavoro non dignitose a causa di caratteristiche strutturali come la bassa redditività, l'alta precarietà e una forte dipendenza dalla manodopera migrante, spesso soggetta a sfruttamento. In Italia, questa problematica si manifesta in modo particolarmente critico attraverso il fenomeno del caporalato: un sistema di intermediazione illecita del lavoro profondamente radicato nell'economia rurale che genera gravi violazioni dei diritti umani. La persistenza di queste pratiche, tragicamente evidenziata da eventi di cronaca, sottolinea l'urgenza di adottare strategie integrate per garantire trasparenza, equità e dignità lungo tutta la filiera agroalimentare. Il passaggio verso un'agricoltura socialmente sostenibile richiede quindi un approccio multidimensionale che coinvolga istituzioni, aziende, società civile e consumatori per trasformare i modelli produttivi e di consumo.A livello istituzionale, si è assistito a un'evoluzione normativa sia in Europa che in Italia. In Italia, accanto a strumenti repressivi, come la Legge 199/2016 contro il caporalato, sono emerse iniziative di governance preventiva (come la Rete del Lavoro Agricolo di Qualità) e l’adesione a standard volontari (SA8000, GlobalG.A.P. GRASP) volti ad assicurare maggiore trasparenza sull'eticità dei processi. Tuttavia, la natura informale dello sfruttamento rende il fenomeno difficile da monitorare sistematicamente. Proprio per questo, la ricerca, dopo avere esaminato la normativa comunitaria e italiana di riferimento, si è posta come primo obiettivo di analizzare come in letteratura sia stata approcciata la problematica del lavoro e quali strumenti analitici siano stati impiegati per misurare il lavoro dignitoso. L'indagine, condotta tramite una revisione sistematica della letteratura, ha rivelato una predominanza di metodologie quantitative, tuttavia spesso limitate dalla scarsità di dati affidabili, e una notevole eterogeneità in indici utilizzati, evidenziando la mancanza di un quadro metodologico consolidato per valutare le condizioni di lavoro in agricoltura.Un'assenza critica nel mercato è quella di una certificazione etica dedicata a prodotti di largo consumo, come l'ortofrutta, particolarmente suscettibili allo sfruttamento. Da qui, l’assenza di informazioni sulla potenziale risposta dei consumatori a questo tipo di certificazione. Questo gap di ricerca è stato affrontato da questa dissertazione che ha investigato le preferenze e i comportamenti dei consumatori italiani. Il primo studio ha dimostrato l'esistenza in Italia di uno spazio di mercato per un'ipotetica certificazione del lavoro equo, rivelando che i consumatori sarebbero disposti a pagare un prezzo premium per prodotti che la espongono. L'analisi ha inoltre evidenziato che la comunicazione gioca un ruolo cruciale: un framing emotivo negativo, che sottolinea le gravi conseguenze dello sfruttamento, è risultato significativamente più efficace nell'aumentare la disponibilità a pagare rispetto a un approccio positivo o neutro. Il secondo studio ha invece approfondito gli antecedenti psicologici dell'intenzione di acquisto, confrontando diversi modelli comportamentali. I risultati indicano che i principali driver sono l'identità personale (percepirsi come consumatore responsabile), la consapevolezza delle conseguenze e l'attribuzione di responsabilità, confermando che le norme morali, mediate da credenze e identità, sono fondamentali per orientare le scelte di consumo etico.Successivamente, l'attenzione si è spostata sui modelli di governance multistakeholder per analizzare la loro capacità di contrastare il fenomeno del caporalato. Quest’ultimo capitolo presenta il caso studio dell'associazione NoCap, che ha messo in piedi un sistema integrato di gestione della manodopera che offre un'alternativa concreta all'intermediazione illecita. L'analisi conferma preliminarmente l'evidenza del caporalato come fenomeno strutturato alla filiera, che non si limita a un atto criminale ma risponde a disfunzioni del mercato del lavoro, richiedendo quindi interventi sistemici per essere contrastato. Dunque, i risultati sull’iniziativa promossa da NoCap mostrano come il progetto sia in grado di interporsi come sistema alternativo migliorando le condizioni dei lavoratori (contratti, alloggi, assistenza) e creando valore per agricoltori e distributori, che utilizzano la certificazione per migliorare la reputazione del marchio. Tuttavia, emergono limiti significativi legati alla scalabilità dell'iniziativa, dovuti a vincoli di risorse e a una penetrazione di mercato ancora di nicchia.In conclusione, questa tesi evidenzia che lo sfruttamento del lavoro in agricoltura è un fenomeno strutturale che richiede strategie integrate, superando il solo approccio repressivo. A livello di policy, è cruciale superare le attuali barriere informative migliorando la raccolta di dati e promuovere modelli di governance multistakeholder che, come NoCap, replichino funzioni virtuose attraverso collaborazioni pubblico-privati. Sul piano manageriale, si segnala come le aziende della filiera possono trasformare la responsabilità sociale in un vantaggio competitivo, sfruttando le certificazioni etiche per migliorare la reputazione del marchio e rispondere a una domanda di mercato latente per prodotti equi, specialmente se comunicati in modo trasparente ed emotivamente coinvolgente.The objective of advancing food systems toward more ethically responsible production constitutes one of the most complex challenges of our time, to the extent that the promotion of decent work has been established as a goal of the 2030 Agenda (SDG 8). The agricultural sector is particularly vulnerable to indecent working conditions due to structural characteristics such as low profitability, high levels of precariousness, and a strong dependence on migrant labour, which is often subject to exploitation. In Italy, this problem manifests in a particularly critical way through the phenomenon of caporalato: a system of illicit labour intermediation deeply rooted in the rural economy that generates severe violations of human rights. The persistence of these practices, tragically highlighted by recent cases reported in the media, underscores the urgency of adopting integrated strategies to ensure transparency, fairness, and dignity along the entire agri-food supply chain. The transition toward socially sustainable agriculture therefore requires a multidimensional approach involving institutions, businesses, civil society, and consumers, with the aim of transforming both production and consumption models.At the institutional level, both European and Italian legislation have evolved. In Italy, alongside repressive tools such as Law 199/2016 against caporalato, preventive governance initiatives have emerged (such as the Rete del Lavoro Agricolo di Qualità), together with adherence to voluntary standards (e.g., SA8000, GlobalG.A.P. GRASP) designed to increase transparency regarding the ethicality of production processes. Nevertheless, the informal nature of exploitation renders the phenomenon difficult to monitor systematically. Precisely for this reason, after examining the National and international legislative framework, the first objective of this research was to analyze how the literature has approached the issue of labour exploitation and which analytical tools have been employed to measure decent work. The investigation carried out through a systematic literature review, revealed a predominance of quantitative methodologies, though often limited by the scarcity of reliable data, as well as a marked heterogeneity in the indices employed. This highlights the absence of a consolidated methodological framework for evaluating working conditions in agriculture.A critical absence in the market is that of an ethical certification specifically dedicated to widely consumed products such as fruit and vegetables, which are particularly susceptible to exploitation. Consequently, there is no information available regarding consumers’ potential response to such certification. This research gap was addressed by the present dissertation, which investigated the preferences and behaviours of Italian consumers. The first study demonstrated the existence of a market space for a hypothetical fair labour certification in Italy, showing that consumers would be willing to pay a price premium for products displaying such a label. The analysis also highlighted that communication plays a crucial role: a negative emotional framing, emphasising the severe consequences of exploitation, proved significantly more effective in increasing willingness to pay than either positive or neutral framings. The second study instead explored the psychological antecedents of purchase intentions by comparing different behavioural models. Results indicate that the main drivers are personal identity (perceiving oneself as a responsible consumer), awareness of consequences, and attribution of responsibility. These findings confirm that moral norms, mediated by beliefs and identity, are fundamental in guiding ethical consumption choices.Subsequently, the focus shifted to multistakeholder governance models in order to assess their ability to counteract the phenomenon of caporalato. The final chapter presents a case study of the NoCap association, which has established an integrated labour management system providing a concrete alternative to illicit intermediation. The analysis confirms the evidence that caporalato is a structural phenomenon within the agri-food supply chain. It is not merely a criminal practice but rather a response to dysfunctions in the labour market, and therefore requires systemic interventions to be effectively challenged. Accordingly, the results on the NoCap initiative show how the project can serve as an alternative system, improving workers’ conditions (contracts, housing, assistance) while simultaneously creating value for farmers and distributors, who use the certification to enhance brand reputation. Nevertheless, significant limitations emerge concerning the scalability of the initiative, linked to resource constraints and its current niche market penetration.In conclusion, this dissertation demonstrates that labour exploitation in agriculture is a structural phenomenon that requires integrated strategies, moving beyond a purely repressive approach. At the policy level, it is crucial to overcome current informational barriers by improving data collection and to promote multistakeholder governance models that, like NoCap, replicate virtuous functions through public–private collaborations. From a managerial perspective, the research underscores how companies in the agri-food chain can transform social responsibility into a competitive advantage, leveraging ethical certifications to strengthen brand reputation and respond to a latent market demand for fair products, particularly when such products are communicated transparently and with emotionally engaging narratives
SrCoO3-δ and SrCo1-xTixO3-δ perovskites as electrocatalytic materials for oxygen evolution reaction in alkaline environment
No full textHere, we report the deposition of SrCoO3-δ perovskites thin films by chemical bath deposition, employed as electrocatalytic layers for oxygen evolution reaction (OER) in alkaline water splitting. The effect of Co excess and Ti-doping on the crystalline structure, composition and electrochemical performances was investigated. The former had effect only on electrochemical performance whilst Ti-doping, above 3 %, induced the formation of a secondary phase. Among all the investigated samples, SrCoO3-δ:Co3O4 (SCO:CB) sample showed the best electrochemical performance toward OER in 1 M KOH aqueous solution, reporting an onset overpotential, ηonset, of 284 mV and a Tafel slope of 59 mV dec−1. In contrast, Ti-doping (i.e. 3 %, SCT:CB 3 sample) drastically improved stability of the electrocatalytic layer, enabling 24 h of continuous operation, demonstrating the effectiveness of doping strategy to enhance SrCoO3-δ perovskites durability. XPS analyses revealed that degradation of electrochemical performance of thin films is related to Sr leaching, even if Ti-doping decreased leached Sr amount improving layers stability
Role of methyl jasmonate in enhancing pigmentation of Tarocco Sant'Alfio (Citrus sinensis [L.], Osbeck) oranges during cold storage
No full textThe aim of study was to evaluate the effectiveness of postharvest methyl jasmonate (MeJA) treatment in enhancing flesh pigmentation and quality in the red orange cv. Tarocco Sant'Alfio, a cultivar known for its late ripening time and limited natural anthocyanin accumulation. Moreover, we tested an image analysis methodology to understand the dynamic of tissue pigmentation and, eventually, we investigate the specific role of individual anthocyanins. Oranges were treated with 0.1 mM MeJA and stored at 8 °C for 28 days. Weekly during storage, physical and organoleptic fruit traits as well as anthocyanins amount and composition, and bioactive compound, were measured. MeJA-treated fruit developed a significantly more intense and earlier red colouration than untreated fruit and exhibited a significantly lower weight loss. Image analysis of the flesh pigmentation gave a valuable insights into the effects of postharvest treatments and the dynamics of pigment accumulation, revealing a marked shift from low to high-intense red distributions in MeJA-treated fruit, in line with the spectrophotometric and HPLC-based anthocyanin quantification. Regression analyses showed that cyanidin 3- O -(6”-dioxalyl)-glucoside, peonidin 3- O -(6”-malonyl)-glucoside, cyanidin 3- O – glucoside, cyanidin 3- O -sophoroside and cyanidin derivatives, were the main contributors to colour development, with moderate to high correlation coefficients with R2 ranging from 0.71 to 0.78, confirming the key role of specific anthocyanins in the observed pigmentation dynamics. These findings underscore the potential of MeJA as an effective postharvest treatment to enhance both the visual appeal and nutritional value of blood oranges with naturally low pigmentation
Synergistic Effects in Matrix-Embedded Alloy Nanoclusters: Advanced Type-I Photosensitizers for Theranostics
No full textA combination of biomedical imaging and photodynamic therapy (PDT) in a
single nanomaterial would be a breakthrough in nanomedicine. However, devising a single
photosensitizer capable of efficient PDT without requiring an external oxygen source under
typically hypoxic tumor conditions, combined with high photostability, biocompatibility, and
renal clearance, remains a challenge. Atomically precise ultrasmall (<2 nm) gold
nanoclusters (AuNCs) are emerging as potential multifunctional biomedicines, encompassing
imaging, diagnosis, and therapy in a single nanoplatform. Herein, we report bioderived
cellulose nanocrystal-supported gold nanoclusters (CNC-AuNCs) with selective mono or
multiheteroatom (Ag, Pd, and Pt) substitution at the core of the nanoclusters. The
replacement of one or more gold atoms significantly modulates their emission wavelengths,
photoluminescence quantum yields, as well as excited-state relaxation kinetics. These
materials can easily penetrate the cells, accumulating in the cytoplasm and emitting bright
luminescence. While the nanocomposites are highly biocompatible, they can produce
reactive oxygen species (ROS) through the formation of free radicals (O2
−· and ·OH) upon
exposure of light. The synergistic effect of the light absorption by the matrix and the diverse excited-state relaxation pathways of the
nanoclusters results in the efficient generation of ROS in variable concentrations, ultimately leading to the complete destruction of
targeted cancer cells via Type-I photodynamic effect. The optimal ROS efficacy combined with minimal cytotoxicity suggests a
universal strategy for developing strong PDT-I agents, paving the way for versatile nanomaterials in theranostic applications
Omnia religiose et cum cura deorum facere debemus. Aspetti della religione e del divino nella declamazione latina
No full textLa dissertazione indaga le rappresentazioni, i ruoli e i significati della religione e del divino nella declamazione latina di età imperiale, concentrandosi sugli Oratorum et rhetorum sententiae, divisiones, colores di Seneca il Vecchio e sulle Declamationes minores pseudo-quintilianee. Attraverso un’analisi mirata dei testi in cui la componente religiosa è centrale, lo studio esplora in che misura, negli esercizi di scuola, sia possibile cogliere la percezione del divino e l’azione degli dèi, il ruolo della ratio religionis nell’argomentazione retorica, lo spazio e l’interpretazione dei responsi oracolari, le funzioni delle pratiche religiose nella declamandi exercitatio e l’utilità di esercitarsi su casi in cui a essere protagonisti sono sacerdotesse e sacerdoti. I risultati evidenziano come la dimensione religiosa rappresenti una componente strutturale del discorso declamatorio, decisiva nel processo formativo del futuro civis Romanus.The dissertation investigates the representations, roles and meanings of religion and the divine in Latin declamation during the Imperial age, focusing on Seneca the Elder's Oratorum et rhetorum sententiae, divisiones, colores and on the pseudo-Quintilian Declamationes minores. Through a targeted analysis of texts in which the religious component is central, the study explores the extent to which, in school exercises, it is possible to grasp the perception of the divine and the action of the gods, the role of ratio religionis in rhetorical argumentation, the space and interpretation of oracular responses, the functions of religious practices in declamandi exercitatio, and the usefulness of practising on cases in which priestesses and priests are the protagonists. The results highlight how the religious dimension represents a structural component of declamatory discourse, decisive in the formative process of the future civis Romanus
A bifurcation phenomenon for the critical Laplace and p-Laplace equation in the ball
No full textWe consider radial positive solutions for a class of quasilinear differential equations
ruled by the p-Laplace differential operator with a critical weighted nonlinearity.
We show that the problem undergoes a bifurcation phenomenon. We provide a new
multiplicity result, even in the classical Laplace case. The proofs use the Fowler
transformation and dynamical systems tools